Select top in postgresql
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postgres postgresql programming sql query find [Edit] EN PostgreSQL - select first N rows 2 contributors 7 contributions 0 discussions 0 points Created by: leila 255 In this article, we would like to show you how to find and selectthe first row from a table in PostgreSQL. Show Quick solution: SELECT "column1", "column2", "columnN" FROM "table_name" LIMIT N;Practical exampleTo show how to select the first N rowsfrom a table, we will use the following table: PostgreSQL - example data used to select the first N rows from the table
Example 1 - select all columnsIn this example, we will select all the information (columns)about the first 3users from the users table. Query: SELECT * FROM "users" LIMIT 3;Output: PostgreSQL - select first 3 rows from a table - result Example 2 - select specified columnsIn this example, we will findthe first 3 users id,name and emailcolumn information. Query: SELECT "id", "name", "email" FROM "users" LIMIT 3;Output: PostgreSQL - select first 3 rows from a table - result Example 3 - first row in some orderIn this example, we will select the first row in some order. Output: PostgreSQL - select first row from a table ordered by name (alphabetical) - result Database preparationcreate_tables.sqlfile: CREATE TABLE "users" ( "id" SERIAL PRIMARY KEY, "name" VARCHAR(100) NOT NULL, "email" VARCHAR(100) NOT NULL, "country" VARCHAR(15) NOT NULL );insert_data.sqlfile: INSERT INTO "users" ("name", "email", "country") VALUES ('Tom', '', 'Poland'), ('Chris', '', 'Spain'), ('Jack', '', 'Spain'), ('Kim', '', 'Vietnam'), ('Marco', '', 'Italy'), ('Kate', '', 'Spain'), ('Nam', '', 'Vietnam'); |